This topic contains a solution. Click here to go to the answer
« previous next »

Author Question: What is the Hubble constant essentially a measure of? a. the number of galaxies in the universe ... (Read 32 times)

ec501234

  • Hero Member
  • *****
  • Posts: 573
on: Jul 27, 2018
What is the Hubble constant essentially a measure of?
 
  a. the number of galaxies in the universe
  b. the expansion of the universe
  c. the age of the Milky Way galaxy
  d. the amount of dark matter in an average galaxy

Question 2

Why are interstellar absorption lines so narrow compared to the width of lines which originate in the photospheres of stars?
 
  What will be an ideal response?


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

juiceman1987

  • Sr. Member
  • ****
  • Posts: 316
Reply #1 on: Jul 27, 2018
Answer to Question 1

b

Answer to Question 2

Much of the interstellar gas is cold, and its density is very low. Because atoms in the ISM move slowly and collide only rarely, interstellar absorption lines are extremely narrow.


ec501234

  • Member
  • Posts: 573
Reply 2 on: Jul 27, 2018
:D TYSM

chereeb

  • Member
  • Posts: 326
Reply 3 on: Yesterday
YES! Correct, THANKS for helping me on my review

« previous next »
 

Did you know?

The lipid bilayer is made of phospholipids. They are arranged in a double layer because one of their ends is attracted to water while the other is repelled by water.

Did you know?

Fewer than 10% of babies are born on their exact due dates, 50% are born within 1 week of the due date, and 90% are born within 2 weeks of the date.

Did you know?

Approximately 25% of all reported medication errors result from some kind of name confusion.

Did you know?

Eating carrots will improve your eyesight. Carrots are high in vitamin A (retinol), which is essential for good vision. It can also be found in milk, cheese, egg yolks, and liver.

Did you know?

The types of cancer that alpha interferons are used to treat include hairy cell leukemia, melanoma, follicular non-Hodgkin's lymphoma, and AIDS-related Kaposi's sarcoma.

Flower part number is a characteristic difference between monocots and eudicots Flower part number is a characteristic difference between monocots and eudicots
A number of tree species can be interconnected by mycorrhizal fungi in the forests of British Columb A number of tree species can be interconnected by mycorrhizal fungi in the forests of British Columb
Spiral Galaxies Seen Nearly Edge On from the Milky Way Spiral Galaxies Seen Nearly Edge On from the Milky Way
Barred Spiral Galaxies Barred Spiral Galaxies
Three possible phylogenies for the australopithecines with Au. anamnesis as the stem ancestor and re Three possible phylogenies for the australopithecines with Au. anamnesis as the stem ancestor and re
A Breathalyzer is used to measure a person's blood alcohol concentration (BAC) A Breathalyzer is used to measure a person's blood alcohol concentration (BAC)
Video: HIV replication/ Replication cycle of HIV

For a complete list of videos, visit our video library